I'm writing a jQuery plugin and I would like my code to take advantage of the jQuery UI show(effect, [options], [speed], [callback]) and hide(effect, [options], [speed], [callback]) functions, which allow you to show and hide elements with a nice animation.

However, I'd also like my plugin to degrade gracefully if jQuery UI isn't available, switching back to use the basic, non-animating show() and hide() functions present in the standard jQuery API.

I'll need to test for the show and hide functions specifically, as even if jQuery UI is available it could potentially be a custom version, without the Effects components included.